Pub Date : 2024-08-29DOI: 10.3103/s0096392524600571
V. V. Adamova, P. A. Ukrainskiy
Abstract
Species distribution modeling (SDM) allows us to define the potential range and identify key factors that determine suitable habitat areas. In this study, predictions are made for the distribution of the European clausilid Cochlodina laminata (Montagu, 1803) in the eastern part of the range using SDM methods. Various algorithms are used to create models, including machine-learning algorithms. As predictors, we select climatic factors and Earth remote sensing (ERS) data (enhanced vegetation index and land cover). Ensemble prediction based on all models shows that the range of C. laminata is V (“wedge”)-shaped and largely coincides with the scheme proposed earlier by I.M. Likharev. However, the potential range proves to be wider in the eastern and southeastern parts. The boundaries of the C. laminata potential distribution are established in the forest-steppe and steppe zones as well as in the Black Sea region and the Caucasus. The use of remote sensing data makes it possible to identify suitable territories in more detail, which is particularly important in the peripheral zones of the range. It is shown that the most significant factors in the distribution of the species in the studied area are the average annual temperature, temperature seasonality, and precipitation of the warmest quarter.
摘要物种分布建模（SDM）使我们能够确定潜在的分布范围，并识别决定适宜栖息地区域的关键因素。本研究采用SDM方法对欧洲栉水母（Cochlodina laminata）（Montagu，1803年）在其分布区东部的分布进行了预测。创建模型时使用了多种算法，包括机器学习算法。作为预测因子，我们选择了气候因素和地球遥感（ERS）数据（增强植被指数和土地覆盖）。基于所有模型的集合预测显示，层叶蕨类植物的分布范围呈 V 形（"楔形"），与 I.M. Likharev 早先提出的方案基本吻合。不过，事实证明东部和东南部的潜在分布范围更大。在森林-干草原和干草原地带以及黑海地区和高加索地区，确定了层叶草潜在分布的边界。通过使用遥感数据，可以更详细地确定合适的地域，这对该地区的边缘地带尤为重要。研究表明，影响该物种在研究区域分布的最重要因素是年平均气温、气温季节性和最温暖季度的降水量。
{"title":"Modeling the Spatial Distribution of the European Land Snail Cochlodina laminata (Gastropoda, Pulmonata, Clausiliidae) in the Eastern Part of the Range","authors":"V. V. Adamova, P. A. Ukrainskiy","doi":"10.3103/s0096392524600571","DOIUrl":"https://doi.org/10.3103/s0096392524600571","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Species distribution modeling (SDM) allows us to define the potential range and identify key factors that determine suitable habitat areas. In this study, predictions are made for the distribution of the European clausilid <i>Cochlodina laminata</i> (Montagu, 1803) in the eastern part of the range using SDM methods. Various algorithms are used to create models, including machine-learning algorithms. As predictors, we select climatic factors and Earth remote sensing (ERS) data (enhanced vegetation index and land cover). Ensemble prediction based on all models shows that the range of <i>C. laminata</i> is V (“wedge”)-shaped and largely coincides with the scheme proposed earlier by I.M. Likharev. However, the potential range proves to be wider in the eastern and southeastern parts. The boundaries of the <i>C. laminata</i> potential distribution are established in the forest-steppe and steppe zones as well as in the Black Sea region and the Caucasus. The use of remote sensing data makes it possible to identify suitable territories in more detail, which is particularly important in the peripheral zones of the range. It is shown that the most significant factors in the distribution of the species in the studied area are the average annual temperature, temperature seasonality, and precipitation of the warmest quarter.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.3103/s0096392524600583
N. V. Vorobjeva, M. S. Muntyan
Abstract
Neutrophil extracellular traps (NETs) are decondensed nuclear chromatin decorated with bactericidal proteins of various cell organelles and performing an effector function aimed at combating pathogens in the inflammatory focus. At the same time, NETs play an important role in the pathogenesis of many autoimmune and inflammatory diseases as well as malignancies. Rabbits are one of the most commonly used species of laboratory animals in medical and biological research. A large number of models of various diseases of the cardiovascular, immune and other human systems have been developed on rabbits. However, in the scientific literature, there is no information about the ability of rabbit neutrophils to undergo NETosis (the programmed cell death in the process of NETs formation) in response to well-known pharmacological stimuli. The purpose of the present study was to investigate in the in vitro system the ability of neutrophils of Soviet chinchilla rabbit to form NETs in response to mimetic of diacylglycerol phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187. To isolate rabbit neutrophils, the Ficoll-Hypaque one-step density gradient centrifugation with modifications was used. Oxidative burst was assessed with luminol-amplified chemiluminescence method, while NETs formation was assessed with immunofluorescence analysis. The study shows for the first time that neutrophils of Soviet chinchilla rabbit do not form NETs in response to PMA but do form traps in response to A23187, and have low levels of oxidative burst in response to PMA, A23187 and chemoattractant N-formyl-methionyl-leucyl-phenylalanine.
{"title":"Peculiarities of Neutrophil Extracellular Traps Formation in Chinchilla Rabbits","authors":"N. V. Vorobjeva, M. S. Muntyan","doi":"10.3103/s0096392524600583","DOIUrl":"https://doi.org/10.3103/s0096392524600583","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Neutrophil extracellular traps (NETs) are decondensed nuclear chromatin decorated with bactericidal proteins of various cell organelles and performing an effector function aimed at combating pathogens in the inflammatory focus. At the same time, NETs play an important role in the pathogenesis of many autoimmune and inflammatory diseases as well as malignancies. Rabbits are one of the most commonly used species of laboratory animals in medical and biological research. A large number of models of various diseases of the cardiovascular, immune and other human systems have been developed on rabbits. However, in the scientific literature, there is no information about the ability of rabbit neutrophils to undergo NETosis (the programmed cell death in the process of NETs formation) in response to well-known pharmacological stimuli. The purpose of the present study was to investigate in the in vitro system the ability of neutrophils of Soviet chinchilla rabbit to form NETs in response to mimetic of diacylglycerol phorbol 12-myristate 13-acetate (PMA) and calcium ionophore A23187. To isolate rabbit neutrophils, the Ficoll-Hypaque one-step density gradient centrifugation with modifications was used. Oxidative burst was assessed with luminol-amplified chemiluminescence method, while NETs formation was assessed with immunofluorescence analysis. The study shows for the first time that neutrophils of Soviet chinchilla rabbit do not form NETs in response to PMA but do form traps in response to A23187, and have low levels of oxidative burst in response to PMA, A23187 and chemoattractant <i>N</i>-formyl-methionyl-leucyl-phenylalanine.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.3103/s0096392524600534
T. V. Poloshevets, V. G. Onipchenko, E. V. Sandalova, T. M. Dzhatdoeva, T. G. Elumeeva
Abstract
The analysis of plants’ functional traits and strategies is the main direction to study the formation mechanisms of the composition and structure of plant communities. Comparison of the mean species trait values with a random sample of a local flora allows one to determine the importance of the trait for the plant community’s formation. Comparison of mean and weighted mean shows the role of the trait in dominance. The aim of this work was to study the role of leaf functional traits and the contribution of Grime’s CSR strategies in the formation of Calamagrostis subalpine meadows, which are the most widespread in the north-western Caucasus. The aboveground biomass in these communities is 384 ± 21 g/m2 (mean and standard error of the mean), the mass of litter of previous years is 393 ± 40 g/m2. The share of grasses in the community is 57.1 ± 2.9%, forbs is 32.9 ± 2.6%, legumes is 8.9 ± 1.4%, and sedges and rushes are 1 ± 0.3%. Three species can be considered as dominants: Calamagrostis arundinacea (26.5% of the total phytomass), Festuca varia (23.3%), and Hedysarum caucasicum (8%). The dominants of community have a higher leaf dry mass, lower leaf water content, and a smaller specific leaf area. The community’s components are characterized by a lower mass of the water-saturated leaf and dry matter content, and a higher specific leaf area. Dominants and components in the community are characterized by a greater contribution of the stress-tolerant strategy.
{"title":"Leaf Functional Traits and Strategies of Plants in Subalpine Calamagrostis Meadows of the North-Western Caucasus","authors":"T. V. Poloshevets, V. G. Onipchenko, E. V. Sandalova, T. M. Dzhatdoeva, T. G. Elumeeva","doi":"10.3103/s0096392524600534","DOIUrl":"https://doi.org/10.3103/s0096392524600534","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The analysis of plants’ functional traits and strategies is the main direction to study the formation mechanisms of the composition and structure of plant communities. Comparison of the mean species trait values with a random sample of a local flora allows one to determine the importance of the trait for the plant community’s formation. Comparison of mean and weighted mean shows the role of the trait in dominance. The aim of this work was to study the role of leaf functional traits and the contribution of Grime’s CSR strategies in the formation of <i>Calamagrostis</i> subalpine meadows, which are the most widespread in the north-western Caucasus. The aboveground biomass in these communities is 384 ± 21 g/m<sup>2</sup> (mean and standard error of the mean), the mass of litter of previous years is 393 ± 40 g/m<sup>2</sup>. The share of grasses in the community is 57.1 ± 2.9%, forbs is 32.9 ± 2.6%, legumes is 8.9 ± 1.4%, and sedges and rushes are 1 ± 0.3%. Three species can be considered as dominants: <i>Calamagrostis arundinacea</i> (26.5% of the total phytomass), <i>Festuca varia</i> (23.3%), and <i>Hedysarum caucasicum</i> (8%). The dominants of community have a higher leaf dry mass, lower leaf water content, and a smaller specific leaf area. The community’s components are characterized by a lower mass of the water-saturated leaf and dry matter content, and a higher specific leaf area. Dominants and components in the community are characterized by a greater contribution of the stress-tolerant strategy.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.3103/s0096392524600546
I. I. Gordeev, Yu. S. Tokarev, E. A. Davydov, I. A. Ekimova, K. A. Drozdov, I. O. Yatsenko, O. V. Yatsenko, N. A. Kochunova, N. V. Bukharova, M. S. Kondratyev, A. A. Miroliubov, I. O. Rozhkova-Timina, S. S. Makeev, D. Yu. Grishina, A. D. Plaksin, A. A. Semenov
Abstract
In August 2023, the combined expedition “Crillon 2023” was accomplished that exploring the terrestrial, aquatic and marine biotopes in the southeastern part of the Crillon Peninsula (Sakhalin Island, Russia). A group of specialists carried out field work in ichthyology, invertebrate zoology, entomology, botany, lichenology, bryology, mycology, parasitology, microbiology, and marine biology. In the previously underexplored territory of the southeastern part of the peninsula, an appreciable amount of data on species diversity was collected, including more than 200 species of plants, 101 species of lichens, 127 species of mosses, and 117 species of basidial macromycetes. Marine coastal communities of the littoral and sublittoral zones were examined, including those achieved by scientific diving techniques. As many as 119 species of invertebrates and 20 species of seaweed were recorded. Information was collected on 20 species of fish, including data on helminth infection. Parasitological studies included the search for microsporidia in all available animal hosts, as well as search for rhizocephalans: parasites of arthropods. Rare and endangered animal, plant and fungal species were found that are included in the Regional and Federal Red Books as well as those not previously recorded from Sakhalin. The preliminary results indicate great potential for further study of the eastern part of the peninsula from the point of view of biological sciences as well as the prospects for establishment of a biological station in this area for long-term research and development.
{"title":"Combined Research Expedition “Crillon 2023”: First Findings and Preliminary Results","authors":"I. I. Gordeev, Yu. S. Tokarev, E. A. Davydov, I. A. Ekimova, K. A. Drozdov, I. O. Yatsenko, O. V. Yatsenko, N. A. Kochunova, N. V. Bukharova, M. S. Kondratyev, A. A. Miroliubov, I. O. Rozhkova-Timina, S. S. Makeev, D. Yu. Grishina, A. D. Plaksin, A. A. Semenov","doi":"10.3103/s0096392524600546","DOIUrl":"https://doi.org/10.3103/s0096392524600546","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>In August 2023, the combined expedition “Crillon 2023” was accomplished that exploring the terrestrial, aquatic and marine biotopes in the southeastern part of the Crillon Peninsula (Sakhalin Island, Russia). A group of specialists carried out field work in ichthyology, invertebrate zoology, entomology, botany, lichenology, bryology, mycology, parasitology, microbiology, and marine biology. In the previously underexplored territory of the southeastern part of the peninsula, an appreciable amount of data on species diversity was collected, including more than 200 species of plants, 101 species of lichens, 127 species of mosses, and 117 species of basidial macromycetes. Marine coastal communities of the littoral and sublittoral zones were examined, including those achieved by scientific diving techniques. As many as 119 species of invertebrates and 20 species of seaweed were recorded. Information was collected on 20 species of fish, including data on helminth infection. Parasitological studies included the search for microsporidia in all available animal hosts, as well as search for rhizocephalans: parasites of arthropods. Rare and endangered animal, plant and fungal species were found that are included in the Regional and Federal Red Books as well as those not previously recorded from Sakhalin. The preliminary results indicate great potential for further study of the eastern part of the peninsula from the point of view of biological sciences as well as the prospects for establishment of a biological station in this area for long-term research and development.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.3103/s009639252460056x
M. M. Surkov, A. A. Mamchur, T. B. Stanishneva-Konovalova, A. B. Rubin, I. A. Yaroshevich
Abstract
Carotenoids belong to one of the most common classes of biological pigments. They are observed in either free form (dissolved in hydrophobic media) or as stoichiometric complexes with protein (carotenoproteins). An interaction between a carotenoid and a protein environment is determined mainly by the molecular conformation and dynamic behavior of a cofactor pigment. In this study, using molecular modeling methods, we have analyzed the whole set of alternative conformational states of cyclic side groups of carotenoids and evaluated the energy effects of their interaction with the conjugated backbone chain. The performed theoretical study resulted in the energy-sorted catalogue of alternative conformational states for biogenic cyclic carotenoids and their optical isomers. Conformational states described in this study can be used for a correct selection of initial conditions for the molecular modeling of carotenoproteins.
{"title":"Theoretical Description of the Puckering States of Cyclic Groups in Carotenoids","authors":"M. M. Surkov, A. A. Mamchur, T. B. Stanishneva-Konovalova, A. B. Rubin, I. A. Yaroshevich","doi":"10.3103/s009639252460056x","DOIUrl":"https://doi.org/10.3103/s009639252460056x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Carotenoids belong to one of the most common classes of biological pigments. They are observed in either free form (dissolved in hydrophobic media) or as stoichiometric complexes with protein (carotenoproteins). An interaction between a carotenoid and a protein environment is determined mainly by the molecular conformation and dynamic behavior of a cofactor pigment. In this study, using molecular modeling methods, we have analyzed the whole set of alternative conformational states of cyclic side groups of carotenoids and evaluated the energy effects of their interaction with the conjugated backbone chain. The performed theoretical study resulted in the energy-sorted catalogue of alternative conformational states for biogenic cyclic carotenoids and their optical isomers. Conformational states described in this study can be used for a correct selection of initial conditions for the molecular modeling of carotenoproteins.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-29DOI: 10.3103/s0096392524600522
E. P. Lukashev, P. P. Knox, M. G. Strakhovskaya, V. Z. Paschenko
Abstract
Increasing volumes of produced antiseptics and disinfectants, which are widely used in medicine, veterinary medicine, the food industry, and everyday life, can pose a serious environmental problem after use. Previously, when studying the action of a number of antiseptics at micromolar concentrations, the authors identified disturbances in the functioning of photosynthetic membranes and phototransforming pigment-protein complexes isolated from them in various representatives of photosynthetic organisms. In this work, to determine the sensitivity of photosynthetic membranes to the action of the cationic antiseptic octenidine, chromatophores of the purple nonsulfur bacteria Rhodobacter sphaeroides labeled with the fluorescent dye 10-N-nonyl acridine orange (NAO) were used. It was shown that the binding of NAO to chromatophores is accompanied by a shift in the maximum emission of the dye from 525 to 640 nm. The “red” fluorescence of NAO associated with chromatophores turned out to be sensitive to the effect of increasing concentrations of octenidine on photosynthetic membranes. Concentrations of the antiseptic at which it leads to degradation of chromatophore structures and a change in the aggregative state of NAO, which can be detected by enhanced “green” fluorescence in the emission spectra of the dye, were established. The properties of NAO as a fluorescent indicator of the functional state of photosynthetic membranes and potential changes that can occur in such systems under the influence of the cationic antiseptic are discussed.
{"title":"10-N-Nonyl Acridine Orange Dye as a Fluorescent Indicator of the Effect of the Antiseptic Octenidine on the Membranes of Rhodobacter sphaeroides Chromatophores","authors":"E. P. Lukashev, P. P. Knox, M. G. Strakhovskaya, V. Z. Paschenko","doi":"10.3103/s0096392524600522","DOIUrl":"https://doi.org/10.3103/s0096392524600522","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>Increasing volumes of produced antiseptics and disinfectants, which are widely used in medicine, veterinary medicine, the food industry, and everyday life, can pose a serious environmental problem after use. Previously, when studying the action of a number of antiseptics at micromolar concentrations, the authors identified disturbances in the functioning of photosynthetic membranes and phototransforming pigment-protein complexes isolated from them in various representatives of photosynthetic organisms. In this work, to determine the sensitivity of photosynthetic membranes to the action of the cationic antiseptic octenidine, chromatophores of the purple nonsulfur bacteria <i>Rhodobacter sphaeroides</i> labeled with the fluorescent dye 10-N-nonyl acridine orange (NAO) were used. It was shown that the binding of NAO to chromatophores is accompanied by a shift in the maximum emission of the dye from 525 to 640 nm. The “red” fluorescence of NAO associated with chromatophores turned out to be sensitive to the effect of increasing concentrations of octenidine on photosynthetic membranes. Concentrations of the antiseptic at which it leads to degradation of chromatophore structures and a change in the aggregative state of NAO, which can be detected by enhanced “green” fluorescence in the emission spectra of the dye, were established. The properties of NAO as a fluorescent indicator of the functional state of photosynthetic membranes and potential changes that can occur in such systems under the influence of the cationic antiseptic are discussed.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142204215","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-25DOI: 10.3103/s0096392524600455
G. V. Morgunova, A. N. Khokhlov
Abstract
The search for and testing of drugs with senolytic activity is a new direction in gerontology. The increasing number of “senescent” cells with age contributes to the development of age-related diseases and chronic non-infectious inflammation. Removing “senescent” cells or suppressing their influence on surrounding tissues seems like a logical step to improve quality of life and possibly prolong it. However, drugs with senolytic and senomorphic activity in model systems induce the development of a number of side effects in clinical trials. In this review, we discuss the main advances in senotherapy, the prospects for the use of senotherapeutics, and the limitations that researchers and clinicians may encounter.
{"title":"Drugs with Senolytic Activity: Prospects and Possible Limitations","authors":"G. V. Morgunova, A. N. Khokhlov","doi":"10.3103/s0096392524600455","DOIUrl":"https://doi.org/10.3103/s0096392524600455","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The search for and testing of drugs with senolytic activity is a new direction in gerontology. The increasing number of “senescent” cells with age contributes to the development of age-related diseases and chronic non-infectious inflammation. Removing “senescent” cells or suppressing their influence on surrounding tissues seems like a logical step to improve quality of life and possibly prolong it. However, drugs with senolytic and senomorphic activity in model systems induce the development of a number of side effects in clinical trials. In this review, we discuss the main advances in senotherapy, the prospects for the use of senotherapeutics, and the limitations that researchers and clinicians may encounter.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140302745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-25DOI: 10.3103/s0096392524600443
A. G. Kizhina, M. S. Maschinskas, E. V. Panova, V. V. Ilyukha
Abstract
The effect of stevia leaf extract, saccharinate, and cyclamate in various dosages on the glycogen content of blood leukocytes in C57BL/6 mice as a necessary substrate for the realization of phagocytosis was studied. An increase in glycogen content was found in all experimental groups treated with sweeteners at a dosage of 10 mg/g of body weight. The effect of sweeteners on the differential leukocyte counts was found only in mice receiving the stevia leaf extract at a dosage of 10 mg/g of body weight manifested as an increase neutrophil-to-lymphocyte ratio (NLR). The data obtained expand our understanding of the metabolism of sugar substitutes in an organism and their influence on physiological systems, in particular, the hematopoietic and immune systems.
{"title":"Effect of Various Sweeteners on Glycogen Content of Blood Leukocytes and Differential Leukocyte Count in C57BL/6 Mice","authors":"A. G. Kizhina, M. S. Maschinskas, E. V. Panova, V. V. Ilyukha","doi":"10.3103/s0096392524600443","DOIUrl":"https://doi.org/10.3103/s0096392524600443","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The effect of stevia leaf extract, saccharinate, and cyclamate in various dosages on the glycogen content of blood leukocytes in C57BL/6 mice as a necessary substrate for the realization of phagocytosis was studied. An increase in glycogen content was found in all experimental groups treated with sweeteners at a dosage of 10 mg/g of body weight. The effect of sweeteners on the differential leukocyte counts was found only in mice receiving the stevia leaf extract at a dosage of 10 mg/g of body weight manifested as an increase neutrophil-to-lymphocyte ratio (NLR). The data obtained expand our understanding of the metabolism of sugar substitutes in an organism and their influence on physiological systems, in particular, the hematopoietic and immune systems.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140302663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-25DOI: 10.3103/s009639252360028x
A. Pronina, R. Grigoryan, A. Makarova, A. Kaplan
Abstract
P300 brain–computer interface (BCI), based on P300 (or P3) event-related potential component, is one of the first BCIs and has various applications, one of which is text typing. This study was conducted to examine visual spatial attention, eye gaze, and event-related potential in a P300 BCI speller. 24 healthy volunteers (7 males) participated in the study, and their electroencephalogram and eye movements were recorded in three different experimental conditions: overt attention, covert attention, and gaze fixation. Results showed that performance was significantly lower in the covert attention condition (5% median accuracy compared to 90% with overt attention). Gaze fixation without allocation of attention yielded an 80% accuracy, despite higher gaze dispersion and lower average gaze duration for fixation characters. Event-related potentials analysis revealed that covert attention led to smaller N1 and P2 components, as well as a later and smaller P3 component. Our findings emphasize the importance of gaze fixation for the performance of classic P300 BCI spellers and suggest gaze shifts as the main source of spelling errors. This information can also be used to design high-performance covert attention BCIs that focus on the P3 in the absence of early exogenous components.
{"title":"Spatial Attention Effects on P300 BCI Performance: ERP and Eye-Tracking Study","authors":"A. Pronina, R. Grigoryan, A. Makarova, A. Kaplan","doi":"10.3103/s009639252360028x","DOIUrl":"https://doi.org/10.3103/s009639252360028x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>P300 brain–computer interface (BCI), based on P300 (or P3) event-related potential component, is one of the first BCIs and has various applications, one of which is text typing. This study was conducted to examine visual spatial attention, eye gaze, and event-related potential in a P300 BCI speller. 24 healthy volunteers (7 males) participated in the study, and their electroencephalogram and eye movements were recorded in three different experimental conditions: overt attention, covert attention, and gaze fixation. Results showed that performance was significantly lower in the covert attention condition (5% median accuracy compared to 90% with overt attention). Gaze fixation without allocation of attention yielded an 80% accuracy, despite higher gaze dispersion and lower average gaze duration for fixation characters. Event-related potentials analysis revealed that covert attention led to smaller N1 and P2 components, as well as a later and smaller P3 component. Our findings emphasize the importance of gaze fixation for the performance of classic P300 BCI spellers and suggest gaze shifts as the main source of spelling errors. This information can also be used to design high-performance covert attention BCIs that focus on the P3 in the absence of early exogenous components.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140883331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-03-25DOI: 10.3103/s009639252460042x
Y. A. Voronina, V. S. Kuzmin
Abstract
The cardiac tissue contains not only beta-type adrenergic receptors (ARs) but also alpha-type ARs (α-ARs). Both types of ARs play a significant role in the regulation of the electrophysiology of cardiomyocytes in different parts of the heart, including the atrioventricular node (AVN). An augmentation of the α1‑AR mediated component of adrenergic signaling causes an impaired conduction of excitation in the heart and the onset of different rhythm disturbances, including AVN-associated arrhythmias. The activation of α1‑AR facilitates anionic transmembrane transport causing electrophysiological changes in myocytes. The purpose of this research is to study the effects of anion/chlorine blockade on the α1-AR-mediated proarrhythmic alteration of AVN functioning. The functional characteristics of AVN, including AVN conduction time, AVN refractoriness, and AVN conduction alterations, were examined via recording of surface electrograms in the Langendorff-perfused isolated rat heart (Wistar, 250 ± 30 g). Phenylephrine (PE, 10 µM) was used as an α1-AR agonist. Probenecid (100 µM) was used as the anion/chlorine transmembrane conductance blocker. The activation of α1-AR by the PE agonist results in a statistically significant increase in atrioventricular delay (AVD, N = 10, p < 0.001) and the effective refractory period (ERP) in the AVN (by 9.8 ± 1.2%, n = 10, p < 0.001). Also, PE induces AV-blocks and oscillations in AVD (N = 10) at stimulation rates close to ERP. Probenecid significantly reduces the range of AVD oscillations during nonstationary conduction in the AVN. In addition, the probenecid attenuates the ERP prolongation caused by PE (107 ± 4 ms, N = 6 and 114.2 ± 5.35 ms, N = 10 in the presence of PE alone and PE with probenecid, respectively), thereby returning its values to the typical level for normal conditions. As a result, probenecid maintains the physiological mode of AVN conduction when α1-ARs are stimulated. This also suggests that chloride channels and anion carriers may contribute to α1-AR-mediated AVN arrhythmias.
{"title":"The Influence of Probenecid on the Proarrhythmic Effects of the Activation of α-1-adrenoceptor in the Atrioventricular Node of the Rat Heart","authors":"Y. A. Voronina, V. S. Kuzmin","doi":"10.3103/s009639252460042x","DOIUrl":"https://doi.org/10.3103/s009639252460042x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The cardiac tissue contains not only beta-type adrenergic receptors (ARs) but also alpha-type ARs (α-ARs). Both types of ARs play a significant role in the regulation of the electrophysiology of cardiomyocytes in different parts of the heart, including the atrioventricular node (AVN). An augmentation of the α<sub>1</sub>‑AR mediated component of adrenergic signaling causes an impaired conduction of excitation in the heart and the onset of different rhythm disturbances, including AVN-associated arrhythmias. The activation of α<sub>1</sub>‑AR facilitates anionic transmembrane transport causing electrophysiological changes in myocytes. The purpose of this research is to study the effects of anion/chlorine blockade on the α<sub>1</sub>-AR-mediated proarrhythmic alteration of AVN functioning. The functional characteristics of AVN, including AVN conduction time, AVN refractoriness, and AVN conduction alterations, were examined via recording of surface electrograms in the Langendorff-perfused isolated rat heart (Wistar, 250 ± 30 g). Phenylephrine (PE, 10 µM) was used as an α<sub>1</sub>-AR agonist. Probenecid (100 µM) was used as the anion/chlorine transmembrane conductance blocker. The activation of α<sub>1</sub>-AR by the PE agonist results in a statistically significant increase in atrioventricular delay (AVD, <i>N</i> = 10, <i>p</i> < 0.001) and the effective refractory period (ERP) in the AVN (by 9.8 ± 1.2%, <i>n</i> = 10, <i>p</i> < 0.001). Also, PE induces AV-blocks and oscillations in AVD (<i>N</i> = 10) at stimulation rates close to ERP. Probenecid significantly reduces the range of AVD oscillations during nonstationary conduction in the AVN. In addition, the probenecid attenuates the ERP prolongation caused by PE (107 ± 4 ms, <i>N</i> = 6 and 114.2 ± 5.35 ms, <i>N</i> = 10 in the presence of PE alone and PE with probenecid, respectively), thereby returning its values to the typical level for normal conditions. As a result, probenecid maintains the physiological mode of AVN conduction when α<sub>1</sub>-ARs are stimulated. This also suggests that chloride channels and anion carriers may contribute to α<sub>1</sub>-AR-mediated AVN arrhythmias.</p>","PeriodicalId":19004,"journal":{"name":"Moscow University Biological Sciences Bulletin","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2024-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140302741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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